<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>凹字型</title>
    <style>
        .ao {
            display: inline-block;
            width: 0;
        }

        .ao::before {
            content: 'love 你 love';
            outline: 2px solid #cd0000;
            color: #fff
        }
    </style>
</head>

<body>
    <div class="ao"></div>
</body>

</html>